Most roads are paved with asphalt, which is produced at an asphalt plant and transported to the construction site in large truck beds such as dump trucks. A difficulty with the transportation operation is that the asphalt tends to stick to the metal surface of the truck bed. The sticking of the asphalt to the bed prevents the asphalt from smoothly sliding out of the bed as the dump truck attempts to discharge its asphalt load. In order to overcome this, workers must coax the asphalt out of the bed using tools. This sticking of the asphalt also affects the tools and other equipment such as rollers.
Asphalt release agents are a well known approach to preventing asphalt from sticking to metallic surfaces. A common release agent used in the past was a hydrocarbon fuel such as ordinary diesel fuel. Such fuels are extremely effective in cutting asphalt in order to prevent it from sticking. However, the reason for their effectiveness is that they combine with and dilute the asphalt. This impairs the structural integrity of the laid asphalt in the roadway. Also, the indiscriminate use of fuel as a release agent contaminates the ground beneath the truck where the agent is applied due to the runoff of excess from the truck onto the ground. For these reasons, the Department of Transportation and many state highway departments have severely restricted the use of fuel as a release agent.
There are other asphalt release agents that are not fuel-based. However, most of these other release agents suffer from some combination of being limited in their effectiveness, being environmentally dangerous, or being expensive. Most of these other release agents also suffer from their complexity in either the delivery, preparation or application steps of utilization. In addition, it is desirable that a release agent contain a corrosion inhibitor to prevent or at least inhibit corrosion of the surfaces to which it is applied, and many of the alternate release agents have no such inhibitor.
It is apparent that there is a need for an asphalt release agent which is effective in preventing the sticking of asphalt to truck beds and other surfaces, is environmentally safe, inhibits corrosion of the surfaces to which it is applied, and is inexpensive.